Ok, so this question has been asked before but it’s usually in the context of CBD vape carts and long term storage.
My analytical lab (Botanicor) does not heat the sample at all before sticking it in their HPLC. They use first homogenize using some sort of stirring and then they use a liquid transfer method, probably a heated micro-pipette.
My most recent distillate crystallizes more than anything I’ve made before (other than Isolate, lol). I know for certain that the samples crystallize before arriving at the lab and I think the fact that they do not dissolve the crystals before analytics is skewing results.
How can I ensure that my samples are being analysed accurately? My samples are overnight-ed and then analysed either the same day or next day.
A few thoughts I’ve had so far:
-Hand warmers could minimize crystallization but only last 12 hours max.
-I read on here once that sonication at 20kHz can prevent crystallization, but I’m not sure how long that lasts
thoughts?
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Here is a photo of how much crystallization I’ve been getting. This took 5 hours in an 80 degree water bath to fully dissolve.
I’m sorry but I am going to trust an analytical chemist that has spent years of their lives running and creating testing protocols based on literature before I EVER question what they are doing.
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Ship it in a vacuum insulated dewar.
Talk to a staff member at Botanicor about sample prep?
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@anon93688
I agree with you but I called them to make sure and to see how they process their samples.
I talked to the QA guy. He acknowledged that it was an issue, and that many people have had problems with it. He also acknowledged that heating the sample first would solve the problem but also invalidate the residual solvent testing. Basically he told me that they are too swamped with work to do custom testing and that heating was difficult to fit into their process flow (I offered to pay extra for heating). Eventually we came to an agreement that I should send high crystallization samples to another lab that will heat it up before testing.
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Does vacuum pressure reduce crystallization or eliminate it?
The other idea I had was to dilute the distillate 1:1 with MCT oil. The only issue then would be explaining to customers why our COA was at half of what it should be.
The vac insulated dewar would just keep the temp from dropping. You could throw a hand warmer in with the sample.
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Great, thank you. I think I’ll evacuate the inside with my vacuum chamber as well. With the hand warmers in there
What testing are you talking about? The only test i could see this maybe being a problem for would be residual solvents. Standard SOP for potency and pesticides I’m used to insists the sample be fully dissolved
@MagisterChemist
Apparently it doesn’t include this step for Botanacor. It’s a cannabinoid potency test. They don’t apply any heat to the sample in case the same sample needs to be analysed for residual solvent.
I agree that the step should be included and would be in any academic lab. These guys are probably processing thousands of samples a day so I guess they don’t heat, only homogenize.
I mean you shouldn’t have to heat. Even if it’s pure crystal, if you put it in an excess of solvent and homogenize vigorously, it will dissolve.
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The problem is that they add solvent after they transfer from the original container. And the transfer method they use is a liquid transfer method so it won’t pick up crystallized material.
So what do they do if they get a solid sample?
I know people who swear that double boiling their carts for 15 mins twice cured this issue.
I have no facts but it’s a hunch.
Powderize and then weigh, followed by dissolving in solvent. QA guy said the issue is that you can’t powderize CBD crystals in distillate, only really break them up. The pippette is selective towards fluids over solids unless the crystals are broken up into very small pieces or dissolved
I don’t think handwarmers would work in vacuum. they probably need oxygen.
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